Mechanism for separating intermixed divided materials



K. DAVIS 1,959,125 MECHANISM FOR SEPARATING INTERMIXED DIVIDED MATERIALS May 15, 1934.

Original File'd Jan. 15, 1923 5 Sheets-Sheet l May'15, 1934. K. DAVIS MECHANISM FOR SEPARATING INTERMIXED DIVIDED MATERIALS .1923 5 Sheets-Sheet 2 Original Filed Jan. 15

K. DAVIS May 15, 1934.

MECHANISM FOR SEPARATING INTERMIXED DIVIDED MATERIALS 1923 5 Sheets-Sheet 3 Original Filed Jan. 13

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MECHANISM FOR SEPARATING INTERMIXED DIVIDED MATERIALS Original Fi ed Jan. 13, 1923 5 Sheets-Sheet 4 K. DAVIS May 15, 1934.

MECHANISM FOR SEPARATING INTERMIXED DIVIDED MATERIALS Original Filed Jan. 13, 1923 5 Sheets-Sheet 5 v ilwuwwta MM Patented May 15, I934 MECHANISM FOR SEPARATING INTER MIXED DIVIDED MATERIALS Kenneth Davis, Ebensburg, Pa. assig'nor, by mesne assignments, to Peale-Davis Company,-v Wilmington, Del. a corporation of Delaware Application January 13 1923,- Serial No. 612,456- Renewed May 11, 1929 7 Claims.

The invention relates to mechanisms for separating intermixed divided materials of diiferent specific gravities, the divisions, pieces or fragments of which vary relatively greatly in size; and in certain of its features, the invention is more especially adapted for cleaning coal, from the intermingled rock and bony without preliminary sizing of these intermixed materials.

Objects and advantages of the invention will be set forth in part hereinafter and in part will be obvious herefrom, or may be ascertained through practicing the inventions.

The invention consists in the novel parts, constructions, arrangements, combinations and improvements herein shown and described.

The accompanying drawings, referred to herein and constituting a part hereof, illustrate one embodiment of the invention and together with the description serve to explain the principles thereof.

Fig. 1 is a side elevation of a mechanism constructed in accordance with, or embodying, the invention;

Fig. 2 is transverse, vertical-section taken substantially on the line 2-2 of Fig. 1;

Fig. 3 is a greatly enlarged, fragmentary elevation of the mechanism shown in the lower central part of Fig. 1, with certain outer parts broken away to show certain interior mechanism;

Fig. 4 is a fragmentary, transverse, vertical section, taken substantially on line 4-4 of Fig. 3, looking in the direction of the arrows;

Fig. 5 is a fragmentary, transverse, vertical section, taken on line 55 of Fig. 3, looking in the direction of the arrows;

Fig. 6 is a fragmentary, horizontal section, taken substantially on line 66 of Fig. 3;

Fig. 7 is a fragmentary detail of the central part of the right-hand end of Fig. 6, showing the connection between the device for regulating the travel of the cleaning table and the controlling lever therefor;

Fig. 8 is a fragmentary detail, in vertical section, taken on line 8-8 of Fig. 6; and

Fig. 9 is a diagrammatic top plan of a coal cleaning or separating plant having a repeating or recleaning mechanism.

The invention is directed to mechanism for separating intermixed, divided materials of different specific gravities, and in certain of its aspects it is especially directed to mechanism for rapidly and eficiently separating such materials having the parts, particles, fragments, or the like, varying relatively greatly in size, and at the same time handling very rapidly and efficiently large quantities of such material relatively to the size of the mechanism.

The term divided, as employed herein, is intended to designate materials which are naturally in separate parts or particles, or which may be crushed, broken, or pulverized, or the like. A par ticular example of such material, and one to which the invention in certain of its aspects is especially adapted, is a mixture of coal, rock, and bony, in the intermixed state in which it comes from the mine. The mechanism in actual work has handled successfully such material ranging in size from 2 inchesdown. Thus, the very tedious, troublesome and expensive preliminary work of sizing, that is, the separation of the divided materials into portions or parts of practically uniform size, within a very small range of Variation, is avoided. It will be understood that the foregoing is explanatory or exemplary, but is not restrictive of the invention.

In connection with the foregoing, certain features of the invention are directed to specific practical applications and developments of the mechanism, such as the collection of dust from the separating or cleaning operation and caused by the vibration and air currents, and the separation and saving of the dust and small particles carried out of the mass of material by the air currents; the regular and properly proportionate feeding of the intermixed materials through the separating or cleaning mechanism; increasing the efficiency and speed of the separating action, as well as to other features thereof.

The present invention is shown applied to a separating mechanism, which is of the general type or kind shown and described in my Patent No. 1,786,739, issued December 30, 1930, and operating generally in the same manner. Various features of the present invention can, of course, be applied to, or utilized with, various other kinds of cleaning or separating mechanisms, such for example as that shown in my co -pending application Serial Number 612,455, filed January 13, 1922, executed concurrently with this application.

Referring now in detail to the present preferred embodiment of the invention, illustrated by way of example in the accompanying drawings, and referring first to the separating or cleaning mechanism proper, the same is shown, in accordance with one feature of the invention, variably inclinable horizontally as may be found desirable or efficient with different kinds of intermixed materials to be operated upon, or with the same kind of materials in different physical states or conditions or sizes.

In said embodied form (Figs. 1,. 2, 3 and 4) a rectangular frame 1 is provided, having parallel, longitudinally disposed side-reaches or members 2 and 3, and crosswise end reaches 4 and 5. This frame is pivotally supported intermediate its ends, and preferably substantially centrally of. the longitudinal side reaches, by suitable means such as a shaft or trunnion 6, journaled respectively in pillars or supports 7 and 8.

Suitable means are provided for regulating the degree of inclination of this frame, and as embodied, near each end of the side reaches 2 and 3 thereof are regulating or positioning devices 9, 10, 11 and 12. Each of these devices is piv otally connected, as at 13, to the frame, and has a bolt and slot connection 14 with a corresponding support 15 extending upwardly from the ground or floor. Thus, the separating mechanism may be inclined as desired to meet the particular requirements in any case.

Referring now to the illustrated and present preferred form of separating devices (Figs. 1, 3, 4 and 5), there is mounted to vibrate or reciprocate longitudinally on the inclinable frame just described a frame carrying the support for the bed of materials undergoing separation.

This frame comprises side frames or strips 16 and 17, and fixed thereto and supported thereby are the vertically disposed, longitudinally extending side walls 24 and 25 of the mechanism for holding the bed of materials undergoing separation. These walls are united at their ends by cross boards or plates 18 and 19, which connect the structure crosswise and also are a part of the inclosing wall for the air currents or blast.

Within the side walls 24 and 25 and preferably extending thefull length of the separating mechanism is a support 20, for the bed or pile of intermixed divided materials undergoing separation. This support is air pervious to permit the passage of air under pressure upwardly through the bed or pile of material upon the support. The support is preferably of varying degrees of perviousness to the air blast longitudinally, the blast usually being strongest at or near the front end and decreasing gradually in force toward the rear end. For this purpose, the support is shown with air apertures 21 therethrough, although other means, such as a support consisting in whole or 'in part of wire gauze, fabric, or the like may be employed.

The support 20 is preferably provided with means for mechanically engaging the particles or pieces of the heavier material which constitutes the lower stratum upon the support, to assist in its mechanical propulsion forwardly and its ejection from the mechanism.

As a matter of convenience herein, the term forwardly would be applied to the right-hand end and direction in Fig. 3, and the word rearwardly to the left-hand end and direction in Fig. 3 herein.

The engaging means, as embodied, comprises upwardly projecting ridges or members 22, arranged transversely upon the upper face of the support 20, and usually extending perpendicularly thereacross. These projections have their rear faces of relatively gentle slope or angle and pro jecting upwardly and forwardly, and have their front faces relatively steep and abrupt, and also preferably projecting upwardly and forwardly, as best shown in Fig. 3.

The support 20 along either side connects with the side walls 24 and 25, already described. There are preferably employed also partitions 26, likewise perpendicular and upwardly projecting from the support 20, longitudinally disposed along the support 20, and parallel to each other and to the side walls 24 and 25. These latter serve principally to prevent useless side movement and travel of the material. In actual construction supports 27 are arranged beneath the separating support or table 20, and preferably in alinement to support the partitions 26.

In the embodied form, and in accordance with certain features of the invention, in effecting the separation of the materials, the supports and the material thereon are given a quick and sharp movement in one direction, preferably longitudinally and forwardly along the support, and also preferably terminating in a sharp, sudden impact, and then preferably a relatively slow move- .ent in the opposite direction, these movements being concomitant with the air blast through the bed of material.

In the embodied form of such means, the sidereaches 16 and 17 of the reciprocable or vibratable frame (Figs. 1, 3 and 5) has set thereinto on their under sides a plurality of bearing plates 38, these plates having recesses therein for receiving the upper beveled edges 39 of supporting, rockable arms or levers 40. The lower beveled ends 41 of the levers or supports 40 rest in recesses in bearing plates 42 set into the upper surfaces of the longitudinal reaches 2 and 3 of the tiltable, non-reciprocable frame. The levers or supports 40 are preferably inclined upwardly and backwardly as shown in Figs. 1 and 3.

Cooperating therewith are a plurality of spring-operating devices, shown herein as rods 49, arranged at the forward ends, respectively, of the side-reaches l6 and 17 of the reciprocable or vibratable frame, being pivoted thereto at the points 50, respectively. These rods 49 work in apertures in plates 51, supported on and projecting from the non-reciprocating frame. Springs 52 are coiled about the rods and are in compression between the plates 51 and nuts 53, which are screw-threaded onto the ends of the rods. The springs 53 thus impel the reciprocable or vibratable separating mechanism upwardly and forwardly.

A suitable stop mechanism cooperates with the foregoing, and according to one feature of the invention, this is preferably regulable or positionable to vary the throw or travel of the separating mechanism. As embodied, a bar 58 is carried on supports 60 at the head of the non-vibrating frame, the bar 58 being provided at either side with beveled or wedge-shaped stops 62 and 63, with which the ends of the side frames 16 and 17 of the reciprocable mechanism impact at the forward end of their travel. Pivoted to the bar 58, preferably centrally thereof at 64 (Fig. 7), is a lever65, which lever is pivoted at 66 upon the non-vibratable cross frame 4. Thus, by moving the bar 58 in one direction or the other by means of the lever 65, the position of the wedge-like stops 62 and 63 will be changed to vary the length of travel or movement of the h vibratable or reciprocable frame. Suitable driving means for the shaft 67 are provided, and as shown, a motor 78 drives from its shaft pulley 78a a belt 79, which also runs over a belt pulley 81, fixed on shaft 82. A belt 83 runs over a small pulley on shaft 82 and over pulley on shaft 67, for speed reduction. A fly wheel 84 is also preferably employed on 67.

With such mechanism, as so constructed and with the cam 73 rotating in the direction of the arrow on Fig. 8, the reciprocable separating mechanism will move relatively slowly downwardly and backwardly, and when the roller 74 rides off the high part of the cam 73, just subsequent to the position shown in Fig. 8, the separating mechanism will move quickly and sharply forwardly and upwardly, under the impulsion of springs 52, and will be stopped suddenly and sharply by impact of the frame members 16 and 17 against the stops 62 and 63, respectively.

The mechanism for providing the air pressure may be of any suitable or convenient form so far as concerns certain features of the invention. As herein shown (Figs. 1, 2, 3, 4 and 5), a chamber 88 is provided, supported by, and extending downwardly from, the non-vibratable frame, this chamber having sidewalls 89 and 90 and end walls 91 and 92, the side and front walls being inclined inwardly and downwardly. Communicating with this chamber, at the rear thereof, is an air pipe 93, which is supplied with air under pressure by any suitable means, such as a fan 94. Pipe 93 has preferably a relatively long flexible portion 95, to provide for freedom in the variably regulable inclination of the separating table. The air chamber may be supplied with any suitable or standard air pressure regulating devices, but these are not shown in the drawings.

An air-tight, flexible juncture is provided between the air chamber and vibratable frame of the separating mechanism, such as a loose bellows-like portion 96 of leather, canvas, or other air-tight, flexible material. Thus, the separating mechanism is free to vibrate without in any wise impairing the action of the air pressure mechanism.

The separating action and process of the mechanism just described is substantially the same as shown in my Patent No. 1,786,739, previously referred to. It may be stated briefly that the material is fed down from above, well toward the forward end of the machine, and is acted upon concurrently by the air blast and the vibrational movement, and is thereby rapidly stratified and separated. The larger pieces of the heavier material sink immediately to the bottom and come into engagement with the support 20, while the lighter and the smaller pieces of the heavier material or materials are lifted or supported at different heights, substantially corresponding to their weights or specific gravities'.

Considering the support in successive, transversely disposed zones (which is merely a convenient assumption for purposes of explanation, as the action is in fact usually substantially symmetrically gradual or graduated along the separating support), this action is repeated rearwardly along the support. That is, the larger pieces of the rock or other heavier material remaining in the intermixed materials at any particular zone or point, sink downwardly into engagement with the support 20, and so on forwardly along the support.

The mechanism is of suflicient length, and the air blast action and the vibrational action are so regulated, that at the rear end of the separating mechanism there is only the lighter or lighest material, completely separated from the intermixture. By the sharp, quick forward motion of the support, assisted by the material-engaging ridges 22 on the face thereof, and by the air action, the rock or other heavy material is mechanically propelled forwardly along the support 20 towards the forward or delivering end for the heavier material.

As the relatively smaller pieces of this heavier material move forwardly and pass into zones or areas of greater air blast action, or pressure, they will not rise again and become intermixed with the lighter materials above them, for the reason that the weight of the materials above them will overcome any buoying tendency of the air blast, and thus the heavier material once deposited, will remain upon the support and be propelled forwardly therealong and be delivered at the forward end thereof.

Means are provided by the invention for feeding the intermixed materials to be separated to the table or separating mechanism, and for regulating the feed thereof exactly to the capacity of the table with the particular materials being operated upon, or with the materials in a particular physical state.

As embodied (Figs. 1 and 3), a hopper 108 is provided, having sidewalls 109 and 110, and having its forward wall 111 backwardly and downwardly inclined towards its rear wall 112, so that at their bottom ends, these two walls are relatively close together, as shown in Fig. 3. Beneath the bottom ends of these walls is a reciprocating feeding platform or plate 115; running on a plurality of rollers 116, journaled upon supports in continuation of the side walls of the hopper. A roller 117 may also bear upon the top surface of the plate 115.

Suitable means for reciprocating the plate are provided, and as embodied a pitman 118 is pivoted at one end 119 to the plate and at its other end 120 to a disc or pulley 121, journaled upon a support 122, mounted upon a floor 123. The pulley or disc 121 is run by a belt 127 running thereover and over a pulley 128 on the shaft of a motor 129. A gate, or other suitable device is provided for regulating the amount of opening above the feed-plate 115, and as embodied, a vertically disposed slide 134 is arranged across the rear wall 112 of the hopper, and is movable vertically to enlarge or diminish the size of the opening beneath the bottom edge of the wall 112.

For this purpose the plate 134 has a bolt and slot support 135 upon the exterior face of the wall 112. Fixed to the plate 134 are geared racks 136, with which mesh gear pinions 137, fixed on a shaft 138, suitably journaled in the frame of the machine and having externally thereto an actuating crank 139. Any suitable indicating means may be provided on the exterior of the mechanism to show the position of the slide 134. A suitable hopper 140 receives the fed intermixed materials from the feeding device 115 and delivers them to the separating mechanism, as shown in Fig. 3.

Means are provided by the invention for settling and gathering the dust set into motion and carried out of the bed of materials by the air action. In the embodied form, this is effected by slowing the air current by permitting expansion thereof, and (Figs. 1, 2 and 3) an expansion chamber is provided above and communicating with the separating mechanism, into which chamber the upwardly traveling air current passes, and within which its velocity is diminished and thereby the dust carried from the bed of materials is separated from the air current and is deposited.

The lower part 160 of this chamber is preferably substantially of the same size as the separating mechanism, and has a flexible, air-tight connection 161 therewith of canvas, leather or other suitable material, to permit the vibratory or reciprocatory motion of the table with respect to the dust settling chamber.

Next above the part of the chamber just described, it is expanded very greatly, relatively, laterally and also rearwardly as shown at 162 in Figs. 1 and 2, the sides thereof being inclined upwardly and outwardly, and also preferably extend ng rearwardly as well.

Above the upwardly and outwardly sloping part of the chamber just described, the upper part 16% of the chamber has preferably vertical walls constituting a fully enlarged space, and this space has a relatively large outlet 165 into the atmosphere, preferably in the rear wall thereof. The outlet is preferably provided with an airpervious screen 166, which permits the free passage of the air, but will arrest and throw down the final fine residue of the floating dust.

The rear portion of this dust recovering chamber preferably extends rearwardly beyond the separating mechanism, as est appears from 1, and the inwardly and downwardly converging part thereof formed by the walls 150, already described, is further diminished by having the rear wall portion 167 downwardly and forwardly in clined.

The bottom of this part of the chamber, as embodied, terminates in inwardly and downwardly converging walls 168, and empties into a spout or chute 169, which discharges the collected dust into the conveying devices for the coal or other .dying tendency and to throw down some of the heavier particles carried by the air currents upon the material undergoing separation.

The embodied form of discharge means for the coal or other lighter separated material, comprises a chute 180 at the rear end of the separating mechanism, which discharges onto a belt 181. The heavier material, such as the rock, is discharged at the forward end through a chute 182 fixed to the vibrating separating mechanism, this chute discharging into a stationary chute 1S4,

wh'ch in turn discharges onto a belt 185. A tail plate 1'79 may be employed when required or desired to maintain the bed of materials at a proper depth, or otherwise in desired condition, at the discharge end for the lighter material.

At the forward end thereof, the separating mechanism is provided with devices for further effect ng, or assisting in, the separating action, and these may be the same or similar to those shown and described in my said copending application Ser. No. 566,639. As embodied, a plate 190 extends across between the side walls of the separating unit, and is spaced above, and preferably parallel to, the bed 20 to form a passageway between for the discharge of the rock or heavier. material.

At the inner or rearward edge thereof, and connecting with the plate 190 is an upwardly extending plate orwall 191. Means are provided for variably positioning the two plates, and as shown, at the sides thereof are triangularly shaped side pieces 192, fitting slidably within the side Walls of the separating mechanism, and having a bolt and slot connection 193 therewith, whereby the device can be raised and lowered with respect to the bed 20, so as to vary the height and thereby the cross-sectional area of the discharge for the heavier material.

Within the passageway formed between the plate 190 and the bed 20, are preferably employed spacing blocks 196, which fill the passage vertically and may be of any desired width, that is, the blocks are removable and replaceable by higher or lower or narrower or wider blocks. At the inner end thereof these blocks have vertically disposed, double bevel faces 197, which direct the material into the passages between the locks. The blocks are preferably in alinement with the partitions 26, and cooperate therewith to direct the material in its travel along and out of the separating mechanism, and to regulate the flow thereof.

There is also preferably provided a gate or closure 200 at the outer or forward end of the discharge passage for the heavier material, this gate being shown hinged at 201, and preferably having a variable or regulable weight 202 to regulate the resistance of the gate to the passage of the air.

The operation of this mechanism is substantially the same as that of the corresponding mechanism in my other application already referred to, Ser. No. 566,639. The plate 190 is vertically positioned to determine the height or area of the discharge passage for the heavy material, in conjunction with the interchangeable blocks 196. As the separating mechanism is vibrated concurrently with the air pressure, the material is gradually separated on the support 20, as previously described herein. During the forward movement and impact of the mechanism the material will pile against the wall 191, and on the reverse movement will be thrown away therefrom.

The mechanism at the forward end of the bed 20, just described, will cause a normal backwardly acting, relatively strong air pressure, which will throw any coal or other lighter material upwardly and ba'ckwardly into the pile of material, but will permit the rock or other heavy material to pass on forwardly. As the pressure increases, it will reach a point where the gate 200 is thrown open, causing a momentary rush of air forwardly, and cooperating with the impact, thereby blowing the accumulated rock out of the separating mechanism into the chute 182. Immediately thereafter the gate 200 will again close, to be opened again when the pressure increases.

The position and regulation of the various parts and members, as to size, weight, position and the like will be varied to effect the highest and most efficient separation with the particular materials operated on, taking also into account the physical state of such materials.

Suitable supporting mechanism will be provided, and, as shown in Fig. 1, the mechanism is housed in a specially constructed building, having side walls 210 and 211 and a floor 212. A plurality of suitably disposed and shaped supporting beams 213 for the mechanism are provided. In this construction the air discharge opening 165 opens into a like aperture in the exterior wall of the building.

In Fig. 9 a mechanism is shown whereby certain of the material, or certain kinds of material or conditions thereof, are subjected to re-separation, preferably in connection with an intermediate crushing operation. An example of this would be in handling coal where an appreciable percentage of the coal is adherent to pieces of rock or bone. In Fig. 9 the separator A discharges the heavier material into a crusher 214, driven from a motor 215 by a belt 216. The crusher discharges the crushed material by a chute 217 into a receptacle or bin 218. From this bin the crushed material is elevated by an inclined flight conveyor 219, which is driven from a motor 220 by a belt 221. The flight conveyor delivers the crushed material into a chute 222, which discharges it into the hopper 140 of the separating unit B.

The invention in its broader aspects is not limited to the exact structure herein shown and described, but changes may be made therefrom within the scope of the accompanying claims without departing from the principles of the invention and without sacrificing its chief advantages.

What I claim is:

1. A mechanism for separating intermixed divided materials of different specific gravities including in combination a separating mechanism comprising means for maintaining a bed of materials undergoing separation, means for forcing an air current through the bed of materials, a dust collecting and expansion chamber directly above the separating mechanism and communicating therewith, the chamber being substantially larger in cross section than the area of the top of the separating mechanism, whereby the upwardly travelling, dust-laden air passes directly into the expansion chamber and deposits its dust, and means for delivering the dust to one of the separated materials.

2. A mechanism for separating intermixed divided materials of dififerent specific gravities including in combination an inclined, transversely ribbed air pervious table, means for passing air upwardly through the table, means for vibrating the table longitudinally, the Lip-stroke of the vibration terminating by impact, whereby the materials are stratified and the heavier materials move upwardly of the table and the lighter materials move downwardly, a dust collecting and expansion chamber above the table and communicating therewith, the chamber being substantially larger in cross section than the top of the table, whereby the upwardly travelling, dustladen air from the table passes directly into the expansion chamber and there deposits its dust, means for longitudinally vibrating the table, for causing the materials to stratify and the strata to move in opposite directions, and means for delivering the dust to one of the separated materials.

3. A mechanism for separating intermixed divided materials of different specific gravities including in combination a separating mechanism adapted to separate the materials through diiference in their specific gravities, means for moving the separating mechanism sharply and quickly in one direction, and means including a laterally movable stop member for regulating the stroke and for terminating said movement by impact.

4. A mechanism for separating intermixed materials of difierent specific gravities, comprising a separating mechanism with an air pervious bottom, the perviousness of which varies progressively toward one end thereof, means for forcing air under pressure through said bottom, means for subjecting the materials to vibration and impact, and means for collecting the dust rising from the materials being separated.

5. A mechanism for separating intermixed materials of different specific gravities, comprising a separating mechanism with an air pervious bottom which is progressively more pervious toward one end thereof, means for longitudinally vibrating the separating mechanism and subjecting it to impact as it is moving toward the more pervious end of the bottom, means for collecting the dust coming from the separating materials, means for delivering the dust to one of the separated materials, and means for forcing air through the bottom.

6. In a dry cleaning apparatus, a pervious reciprocating deck, means for feeding a fiowing sheet of granular material thereacross, means for passing a moving column of air upwardly thru the sheet, a hood located above the deck containing an air settling chamber bounded on its underside by the sheet of material and means for withdrawing air from said hood at a point above the settling chamber and widely separated from the sheet of material, and a closure between the hood and the deck atall points about its periphery except the space thru which the sheet of material enters and is discharged from the deck, the hood being fixed in position independent of the movement of the deck.

7. A mechanism for purifying coal including in combination an air pervious deck, means for feeding to and maintaining upon the deck a bed of raw coal containing pieces and particles varying relatively greatly in size, means for vibrating said bed, means for passing lifting and loosening air currents through the bed, means for controlling said vibrating and air-supplying means to eifect a gradual and progressive stratification of the coal and impurities and means for separately delivering settled impurities and purified coal, a dust-collecting chamber above the deck and communicating therewith through an opening substantially co-extensive with the area of the bed, said chamber having a portion of relat-ively great cubic capacity extending for a relatively great distance above the bed and also extending horizontally beyond the limits of said opening, whereby the dust-laden air rises directly from the bed and loses its momentum in the enlarged portion of the chamber, and means in the enlarged portion of the chamber and above the bed for collecting the precipitated dust.

KENNETH DAVIS. 

